Abrasive liquid detergent compositions



United States Patent 3,520,818 ABRASIVE LIQUID DETERGENT COMPOSITIONS Cushman Merlin Cambre, Cincinnati, Ohio, asslgnor to The Procter & Gamble Company, Cincinnati, Ohio, a corporation of Ohio No Drawing. Filed Dec. 20, 1966, Ser. No. 603,098 Int. Cl. Clld 9/14, 9/20, 9/32 U.S. Cl. 252113 13 Claims ABSTRACT OF THE DISCLOSURE Liquid detergent compositions suitable for cleaning hard surfaces which are capable of supporting particulate material, e.g., abrasives; said detergent compositions contain water, soap, zwitterionic synthetic detergents and tetrapotassium pyrophosphate, and can, additionally, contain borate ions and inter polymers of methyl vinyl ether and maleic anhydride esterified with a zwitterionic synthetic detergent.

This invention relates to liquid detergent compositions adapted for cleaning hard surfaces. More particularly, this invention relates to a liquid detergent composition having a yield value of from about to about 200 dynes per square centimeter.

There has been an increasing demand for liquid detergent compositions adapted for cleaning hard surfaces. These liquid detergent compositions are provided in convenient form and are specially formulated for this particular cleaning application. To obtain optimum cleaning and consumer acceptance, these detergent compositions must be homogeneous and easily pourable. These compositions, when intended for the retail consumer market, should maintain their homogeneity during ordinary periods of storage and use, e.g., up to four months, and should have acceptable freeze-thaw characteristics. It is highly desirable that liquid detergent compositions for cleaning hard surfaces should exhibit Bingham Plastic characteristics, that is, they should exhibit a substantial yield value in order to hold particulate material in suspension in the detergent composition and prevent that particulate material from settling to the bottom of the container.

When these liquid detergent compositions are intended for industrial applications, excellent product stability, as described above, is not as important as it is in the retail consumer market. In industrial applications, phases can be recombined and particulate material redistributed before use. However, even these products should be stable for at least a 24 hour period.

Liquid detergent compositions containing a combination of alkali metal soaps, ethanol amides and potassium pyrophosp'hates are known (see US. Pat. 3,234,138). Although liquid detergent compositions containing alkali metal soaps, amides and phosphates exhibit useful properties, these compositions also have some disadvantageous features. For example, when particulate materials are added to these compositions and the compositions are then subjected to ordinary storage conditions, they may separate into two layers. As these liquid detergent compositions separate, they lose their ability to support particulate material and, accordingly, the particulate material precipitates. As another example, a portion of the amides in these compositions is hydrolyzed to soap if the compositions are subjected to high storage temperatures, e.g., 110 F. As the amide hydrolyzes, the liquid detergent compositions separate and lose their Bingham Plastic characteristics. Again, the particulate material in these compositions is deposited on the bottom of the respective containers.

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Accordingly, it is an object of this invention to provide liquid detergent compositions which exhibit Bingham Plastic characteristics and which are stable for protracted periods of time. It is a further object of this invention to provide liquid detergent compositions which remain stable when subjected to both depressed and elevated storage temperatures. A still further object of this invention is to provide Bingham Plastic, liquid detergent compositions in which particulate material will not settle to the bottom of the containers when the compositions are stored for protracted periods of time. Yet another object of this invention is to provide liquid detergent compositions which have acceptable freeze-thaw characteristics. Another object of this invention is to provide liquid detergent compositions which exhibit Bingham Plastic characteristics and which do not contain amides. It is another object of this invention to provide a detergent composition in convenient, pourable form.

Still further objects and the entire scope of applicability of the present invention will become apparent from the detailed description given hereinafter. It should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only since various changes and modifications within the spirit and scope of this invention will become apparent to those skilled in the art. All parts, percentages and ratios set forth herein are by weight.

It has surprisingly been discovered, according to the present invention, that the foregoing objects are obtained with an opaque, liquid detergent composition which is substantially free of amides and hydrotropes and which has a yield value of from about 10 to about 200 dynes per square centimeter consisting essentially of, by weight of the finished composition,

(1) soap having an iodine value of from about 0 to about 4 5; the cation of said soap being selected from the group consisting of monoethanolammonium, diethanolammoniaum and triethanolammonium cations; said soap having an acyl chain containing from about 14 to about 22 carbon atoms;

(2) a zwitterionic quaternary ammonio synthetic detergent having the general formula:

wherein R is an alkyl chain containing from about 10 to about 18 carbon atoms and -R" is a radical selected from the group consisting of ethylene and hydroxyethylene; the ratio of soap to the zwitterionic synthetic detergent ranges from about O.8:1.0 to about 1.2:1.0 and the combined weight of the soap and the zwitterionic synthetic detergent ranges from about 8% to about 20% by weight of the finished composition;

(3) from about 10% to about 17% of tetrapotassium pyrophosphate;

(4) from 0% to about 3% borate ions;

(5) from 0% to about 0.5% of an interpolymer of methyl vinyl ether and maleic anhydride in a molar ratio of about 1:1 having a specific viscosity of from about 0.1 to about 3.5 which is esterified with from about 0.1 to about 1 part by weight of a Zwitterionic synthetic detergent per part of the interpolymer, said zwitterionic synthetic detergent having the general formula wherein R is an alkyl chain containing from about to about 18 carbon atoms;

(6) from 0% to about 40% of :an insoluble, particulate material having particle diameters ranging from about 1 micron to about 200 microns and a specific gravity of from about 0.5 to about 3.0;

(7) from about to about 85% water; and

(8) sufficient strong base to adjust the pH of the composition to from about 7.5 to about 13.0.

The liquid detergent composition of this invention will be characterized, in its entirety, at this juncture in order to facilitate a better understanding of the individual components and their functions in these liquid detergent compositions.

The liquid detergent compositions of this invention will suspend insoluble, particulate materials which meet the particle size and specific gravity specifications set forth above. Compositions such as these are generally described as being Bingham Plastic or Real Plastic. These Bingham Plastic compositions possess a yield value and, therefore, provide resistance to flow forces or stresses. It is this reitarlce to flow that maintain the particulate material in suspension.

The yield value is the minimum force required to initiate fiow. It is measured as the intercept on the shearing stress axis of a rate of shear versus shearing stress diagram. Because it is usually not known whether a system behaves in a truly plastic manner at low shear rates, the measurement of exact yield values is quite difficult. A close approximation can be obtained by using a Brookfield viscometer. The yield value is estimated, in dynes per square centimeter, by the following relationships:

Viscosity at 0.5 r.p.m.-Viscosity at 1 r.p.m. 100

This relationship represents an extrapolation of the shear curve to 0 r.p.m. since an absolute shear stress cannot be measured at 0 rpm.

It is believed that the liquid detergent composition of this invention is a suspension of a mesomorphic neat phase (discrete phase) suspended in an isotropic medium which is probably lye (continuous phase). The physical structure of the system is highly oriented. Apparently, it is this high degree of orientation that imparts the yield value to the system.

The essential individual components of this invention are soap, zwitterionic synthetic detergents, tetrapotassium pyrophosphate and water. The soap, the zwitterionic synthetic detergent and the tetrapotassium pyrophosphate are Yield Value the primary cleaning or detergent components of this composition. In preferred embodiments of this invention, borate ions and interpolymers of methyl vinyl ether and maleic anhydride esterified with a zwittterionic synthetic detergent, as hereinafter defined, can be added to the liquid detergent composition of this invention. All of these compositions are capable of suspending particulate materials of the hereinafter specified specific gravity and particle size and, accordingly, these particulate materials can be included as components of these liquid detergent compositions.

The soap utilized in the liquid detergent composition of this invention has an iodine value of from about 0 to about 45, a cation selected from the group consisting of monoethanolammonium, diethanolammonium and triethanolammonium, and an acyl chain length of from about 14 to about 22 carbon atoms and, preferably, from about 16 to about 22 carbon atoms.

The iodine value, or degree of saturation, of the soap is very important in this invention. If the iodine value of the soap is over 45, detergent systems with unacceptably low yield values and poor phase stability are Obtained. When the iodine value is between and 45, the product is acceptable for industrial uses, that is, the product is stable for at least 24 hours. When the product is to be sold in the retail consumer market, it is preferred that the 4 iodine value of the soap utilized in these compositions be from about 0 to about 35 to obtain maximum product stability and acceptable yield values.

The cations of the soap component of this invention are selected from the group consisting of monoethanolammonium, diethanolammonium or triethanolammonium. If ammonium soap or alkali-metal soap is utilized in this invention, the compositions may separate into two layers and, generally, the compositions have unacceptably low yield values. Table I, set forth hereinafter in Example V, illustrates the importance of the cation of the soap component. The monoethanolammonium and diethanolammonium soap compositions are more stable over protracted periods of time than the triethanolammonium soap compositions and are, therefore, highly preferred.

The acyl chain length of the soap utilized herein is from about 14 to about 22 carbon atoms. A particularly preferred chain length distribution is obtained by utilizing tallow soap. Of course, other saponifiable, natural and synthetic materials having acyl chain lengths of from about 14 to about 22 carbon atoms and mixtures of these materials can be used in making the soap for use in this invention.

From about 4% to about 10% of the above-described soap by weight of the finished detergent composition is utilized in the detergent compositions of this invention. In a preferred embodiment, the above-described soap is utilized in these compositions in amounts of from about 4.5% to about 8% by weight of the finished composition.

The zwitterionic quaternary ammonio synthetic detergent of this invention has the following structural formula:

wherein R is an alkyl radical containing from about 10 to about 18 carbon atoms and R is a radical selected from the group consisting of ethylene and hydroxyethylene. It is preferred that R be hydroxyethylene.

The zwitterionic synthetic detergent described above is utilized in this invention in amounts of from about 4% to about 10% by weight of the finished detergent composition. It is preferred that the zwitterionic synthetic detergent be utilized in amounts of from about 4.5 to about 8% by weight of the finished composition.

It is important in the practice of this invention to maintain the weight ratio of soap to zwitterionic synthetic detergent in the range between from about 0.8:1.0 to about 1.2:1.0. When the soap to zwitterionic ratios do not fall within these limits, the detergent compositions of this invention may have unacceptably low yield values if too much soap is utilized or they may separate into two layers at room temperature if too much zwitterionic synthetic detergent is utilized. The combined weight of the soap and zwitterionic synthetic detergent should range from about 8% to about 20% by weight of the finished detergent composition. It is preferred that the soap to zwitterionic synthetic detergent ratio be about 1:1 and the combined weight of the soap and zwitterionic synthetic detergent be from about 9% to about 16% by weight of the finished detergent composition.

Tetrapotassium pyrophosphate is added to the detergent compositions of this invention as a cleaning aid and as a pH buffer. Tetrapotassium pyrophosphate is utilized herein, in preference to other detergency builders, because of its good cleaning characteristics and excellent solubility characteristics. The liquid detergent compositions built with tetrapotassium pyrophosphate also exhibit excellent stability characteristics over a wide range of temperatures.

From about 10% to about 17% of tetrapotassium pyrophosphate by weight of the finished detergent composion is utilized in this invention. To maximize stability and optimize the cleaning characteristics of the liquid detergent compositions, from about 12% to about 15.5% tetrapotassium pyrophosphate should be utilized herein.

The liquid detergent compositions comprising soap, zwitterionic synthetic detergents and tetrapotassium pyrophosphate, described above, clean well and have yield values which are adequate to suspend particulate material. However, the freeze-thaw properties and stability properties of these compositions can be improved and the yield value raised by the addition of other components as will be described hereinafter.

Borate ions can be added to these detergent compositions, in this preferred embodiment, to improve low temperature stability properties and to raise the yield value. The borate ions can be introduced into the detergent composition in several forms, e.g., anhydrous sodium borate, sodium borate pentahydrate, and sodium borate decahydrate. Sodium borate decahydrate is preferred for use herein as it is readily available to the detergent industry. When the anhydrous or hydrated borate compounds are utilized, they ionize and the borate ions are then present in these liquid detergent compositions.

At low temperatures, large emulsion particles or globules may form in and precipitate from the liquid detergent compositions hereinbefore described which do not contain borate ions. The yield values of these liquid detergent compositions may also be lowered at low temperatures with the concomitant precipitation of a minor portion of the particulate material. The addition of the hereinafter specified amounts of borate ions prevents the formation of these large emulsion particles at low temperatures and maintains the yield values of these compositions at an acceptable figure.

It has been found that from 0% to about 3% borate ions, by weight of the finished detergent composition, can be utilized in this invention. It is preferred that from about 1.75% to about 2.25% borate ions be utilized. This preferred range corresponds to about 4.3% to about 5.5% sodium borate decahydrate by weight of the finished composition.

Low temperature stability of this liquid detergent composition can also be improved by adding interpolymers of methyl vinyl ether and maleic anhydride which have been esterified with the hereinbefore described zwitterionic synthetic detergent wherein R is hydroxyethylene. It is believed that the interploymers help create more highly oriented systems wherein the particles or globules of the discrete phase are held in substantially the same position relative to the other discrete phase particles. The results attributable to this added orientation are illustrated by the following example:

Downward pressure is applied to two samples of the liquid detergent composition of this invention, one of which contains the esterified interpolymer and one of i which does not contain the esterified interpolymer. When observed under a micrsocope, part of the c ntinuous phase of the liquid detergent composition containing no esterified interpolymer split out and formed lakes or large areas containing no discrete phase. The discrete phase also conglomerated into fairly large masses and actually glided through the lakes of continuous phase. The liquid detergent composition containing the esterified interpolymer showed no evidence of this phenomenon. Shear and low temperatures produce this same phenomenon in samples containing no esterified interpolymer.

The interpolymer utilized herein has the following unit structural formula:

The interpolymer is comprised of vinyl ether and maleic anhydride in a molar ratio of about 1:1. The interpolymers suitable for use in this invention have a specific viscosity of from about 0.1 to about 3.5 and, preferably, have a specific viscosity of from about 0.1 to about 0.5.

The specific viscosity, as used herein, is determined from a solution of 1 gram of the interpolymer in ml. of methyl ethyl ketone at 25 C. As is well known in the art, molecular weight is directly related to the specific viscosity.

The interpolymer is esterified with a zwitterionic synthetic detergent having the following formula:

wherein R contains from about 10 to about 18 carbon atoms. From about 0.1 to about 1.0 parts by weight of additional zwitterionic, as hereinbefore defined, should be utilized per part of interpolymer in this esterification process.

The esterification reaction is carried out at elevated temperatures, e.g., from about F. to about 200 F. In most cases, some electrolyte, such as sodium chloride, is present when the interpolymer is being esterified. The electrolyte, however, is not necessary in this prOcess.

The interpolymer esterification mechanism is believed to follow the route outlined below:

From 0% to about 0.5% of this esterified polypolymer is utilized in this invention. It is preferred that from about 0.1% to about 0.25% of this esterified interpolymer be used in the composition of this invention.

The insoluble, particulate material utilized in this invention can comprise abrasives, bactericides or other insoluble, particulate material having a particle size diameter ranging from about 1 to about 200 microns and a specific gravity of from about 0.5 to about 3.0. It is preferred that the diameter of the particles range from about 2 microns to about 60 microns and that the specific gravity range from about 1.0 to about 2.8. The abrasives which can be utilized in this invention include, but are not limited to, pumice, pumicit-e, talc, silica sand, china clay, bentonite, diatomaceous earth, whiting, feldspar and aluminum oxide. Quartz is the preferred abrasive for use herein. Bactericides which can be utilized herein include trifluoromethyl dichlorocarbanilide and diphenyl bismuth acetate.

In the practice of this invention, from 0% to about 40% of the composition of this invention is comprised of insoluble particulate material. It is preferred, however, that from about 7% to about 15% by weight of the finished composition be insoluble, particulate material.

From about 25% to about 85% of this composition is comprised of water. It is preferred that water comprise from about 55% to about 70% by weight of the finished composition to optimize yield values and cleaning characteristics of the finished product. It is also preferred that soft water be utilized in this invention.

The pH of the composition is adjusted to from about 7.5 to 13, preferably from about 9 to 12, by adding a strong base. The most desirable strong bases for use herein are sodium hydroxide and potassium hydroxide. Potassium hydroxide is highly preferred. In the preferred pH range, the liquid detergent compositions of this invention have higher yield values and greater stability.

Materials which make the composition of this invention more attractive or more effective may be added if they do not significantly alter the excellent physical properties of this composition. The following materials are mentioned merely by way of example: soluble sodium carboxymethyl cellulose, tarnish inhibitors such as benzotriazole or ethylenethiourea, brighteners, fiuorescers, dyes, bluing agents, perfumes, bactericides and corrosion inhibitors.

Hydrotropes such as sodium or potassium xylene sulfonate, toluene sulfonate, and benzene sulfonate, should not be present in the compositions of this invention. Even very small amounts of these hydrotropes solubilize the discrete phase into the continuous phase. The detergent composition, thus, becomes a one-phase solution and loses its Bingham Plastic characteristics with concomitant precipitation of insoluble, particulate material, e.g., abrasive. The composition, in this condition, is aesthetically undesirable and not saleable on the retail consumer market or the industrial market.

The following examples merely serve to illustrate the invention in specific detail and, when read in conjunction with the foregoing description, will aid in determining the full scope of the present invention. The examples are merely illustrative and are not intended to restrict this invention.

EXAMPLE I An interpolymer of methyl vinyl ether and maleic anhydride, in a molar ratio of about 1:1 having a specific viscosity, as hereinbefore defined, of about 0.4, was esterified with a zwitterionic synthetic detergent having the following formula wherein R contained a mixture of alkyl radicals con taining from to 18 carbon atoms. Ten parts of the interpolymer were mixed with 3 parts of a zwitterionic synthetic detergent solution and 87 parts of soft water. The 30% zwitterionic solution contained 6% electrolyte, i.e., sodium chloride, 30% zwitterionic synthetic detergent as hereinbefore described and 64% soft water. Therefore, the interpolymer was esterified with 0.27 part of the zwitterionic per part of the interpolymer. The above described mixture was maintained at a temperature of 160 F. while being agitated for 40 minutes at which time esterification was completed.

In a separate mixer, 300 parts of commercial borax (sodium borate decahydrate) were added to 1888 parts of soft water. This mixture was maintained at a temperature of about 140 F. while being agitated. Sixty parts of the esterified interpolymer were then added to the mixture followed by 99.6 parts of diethanolamine. 260 parts of tallow fatty acid having an iodine value of 30 were also added to the mixture. Agitation was continued until neutralization of the tallow fatty acid was completed, i.e., the tallow soap had been formed. 1385 parts of a tetrapotassium pyrophosphate solution were then slowly poured into the mixture to form a creamy emulsion. The tetrapotassium pyrophosphate solution comprised water and 65% tetrapotassium pyrophosphate.

To this emulsion were added 600 parts of quartz having a specific gravity of 2.65 and particle diameters ranging from about 2 microns to about 60 microns. The emulsion was agitated until the quartz was uniformly distributed in the emulsion. At this time, 1241 parts of the 30% zwitterionic solution hereinbefore defined were added. The pH of the resulting emulsion was adjusted to about 10.5 by adding 137 parts of an aqueous solution containing of potassium hydroxide. The resulting emulsion had a yield value of 81 and was smooth and homogeneous.

The final detergent composition was opaque and easily pourable and consisted essentially of, by weight of the finished composition,

The remainder of the composition, i.e., about 1.5%, was comprised of sodium chloride. The sodium chloride is, however, not necessary to the proper functioning of this invention.

Bottles were filled with the abrasive, liquid detergent composition and stored under varying conditions for nine months. The bottles were separately stored under conditions of 40 F., 60 F., F., F. and F. At the end of this storage period, there were no signs of layering and no precipitation of the particulate material.

Two samples were frozen solid at 0 and maintained at this temperature for 24 hours. These frozen samples were then separately stored at temperatures of 80 F. and 40 F., respectively, for two months. At the end of this period, neither sample had separated into layers and no quartz had precipitated from the emulsion.

These abrasive, liquid detergent compositions were especially suited for cleaning hard surfaces. They can be used as full-strength compositions for heavy-duty cleaning or they can be diluted with water for the lighter cleaning jobs.

EXAMPLE H An abrasive, liquid detergent composition is prepared from the following components according to the procedure of Example I.

Component: Parts by weight Soft water 1838 Tetrapotassium pyrophosphate solution (see Example I) 1300 Diethanol amine 99.6 Tallow fatty acid (neutralized to diethanolammonium soap) 260 30% zwitterionic synthetic detergent solution (see Example I) 1241 Quartz (see Example I) 600 1 Potassium hydroxide solution to pH of 10.5 137 The finished detergent composition is stable and has a yield value of about 75. The composition does not separate on standing for a period of about one month.

EXAMPLE III Abrasive, liquid detergent compositions are prepared from the following components according to the procedure of Example I.

Parts by weight Com o- Com 0- Component sitiori A sitiori B Soi't water 1, 888 1, 888 Tetrapotassium pyrophosphate solution (see Example I) 1, 300 1, 300

Diethanol amine 99. 6 99. 6 Tallow fatty acid (neutralized to diethanolammonium soap 260 260 30% zwitterionic synthetic detergent solution (see Example I) 1, 241 1, 241

Borate ions (sodium borate 'dtiiri dr'i) Esterified interpolymer (see Example I)...

Quartz (see Example I) 600 600 Potassium hydroxide solution to pH of 10.5

(see Example I)- 137 137 These detergents are stable and have yield values of about 7.5. These compositions do not separate on standing for about one month.

EXAMPLE IV When the following components are substituted for their counterparts in any of the previous examples, substantially the same results are obtained in that the particulate material does not precipitate and the liquid detergent composition does not separate into layers under ordinary storage conditions.

The following fatty acids are substituted for the tallow fatty acid of Example I: stearic acid, myristic acid, palmitic acid, rapeseed acid, and a mixture of 20% myristic fatty acid and 80% tallow fatty acid. Stoichiometric equivalents of monoethanolamine or triethanolarnine are substituted for the diethanolamine of Example I. The zwitterionic quaternary ammonio synthetic detergent of Example I is replaced by a similar zwitterionic synthetic detergent wherein R" is ethylene instead of hydroxyethylene.

The following insoluble, particulate materials are substituted for the quartz in Example I: pumice, pumicite, talc, china clay, aluminum oxide, feldspar, whiting, bentonite, silica sand, diphenyl bismuth acetate, trifluoromethyl dichlorocarbanilide. All of these particulate materials have particle sizes ranging from 1 micron to 200 microns and specific gravities ranging from 0.5 to 3.0. The particulate material does not precipitate.

EXAMPLE V The liquid detergent compositions of Table I are all comprised of TABLE I Yield Percent Catlon pH value separation Ammonium 10. 16 35 Potassium 10. 5 8 35 Monoethanolammonimm. 10. 45 50 None Diethanolammonium 10. 5 81 None Triethanolarmnonium 10. 3 7 None None of the substituted ammonium soap compositions split and all of these compositions had acceptable yield values. The ammonium soap composition had a barely acceptable yield value but split into two separate layers in a 24 hour period which, of course, is unacceptable. The potassium soap composition had an unacceptable yield value and, additionally, split into two separate layers in a 24 hour period.

The foregoing description of the invention has been presented describing certain operable and preferred embodiments. It is not intended that the invention should be so limited since variations and modifications thereof will be obvious to those skilled in the art, all of which are within the spirt and scope of this invention.

What is claimed is:

1. A stable, liquid detergent composition which is substantiall free of amides and hydrotropes and which has a yield value of from about 10 to about 200 dynes per square centimeter consisting essentially of, by weight of the finished composition,

(1) tallow fatty acid soap having a iodine value of from about 0 to about 45; the cation of said soap being selected from the group consisting of monoethanolammonium, diethanolammonium and triethanolammonium cations;

(2) a zwitterionic quaternary ammonio synthetic detergent having the general formula wherein R is an alkyl chain containing from about 10 to about 18 carbon atoms and R is a radical selected from the group consisting of ethylene and hydroxyethylene; the ratio of soap to the zwitterionic synthetic detergent ranges from about 08:10 to about 1211.0 and the combined weight of the soap and the zwitterionic synthetic detergent ranges from about 8% to about 20% by weight of the finished composition;

(3) from about 10% to about 17% of tetrapotassium pyrophosphate;

(4) from about 0% to about 3% borate ions;

(5) from about 0% to about 0.5% of an interpolymer of methyl vinyl ether and maleic anhydride in a molar ratio of about 1:1 having a specific viscosity of from about 0.1 to about 3.5 which is estreified with from about 0.1 to about 1 part by weight of a zwitterionic synthetic detergent per part of the interpolymer, said zwitterionic synthetic detergent having the general formula:

wherein R is an alkyl radical containing from about 10 to about 18 carbon atoms;

(6) from 0% to about 40% of water insoluble abrasives having particle diameters ranging from 1 micron to about 200 microns and a specific gravity of from about 0.5 to about 3.0;

(7) from about 25% to about water; and

(8) sufficient strong base to adjust the pH of the composition of from about 7.5 to about 13.0.

2. The composition of claim 1 wherein the soap has an iodine value of from 0 to about 35 and the cation of the soap is selected from the group consisting of monoethanolammonium and diethanolammonium cations.

3. The composition of claim 1 wherein the soap comprises from about 4% to about 10% "by weight of the finished detergent composition and the zwitterionic synthetic detergent comprises from about 4% to about 10% by weight of the finished detergent composition.

4. The composition of claim 1 wherein the soap comprises from about 4.5% to about 8% by weight of the finished detergent composition and the zwitterionic synthetic detergent comprises from about 4.5% to about 8% by weight of the finished detergent composition.

5. The composition of claim 1 wherein the zwitterionic quaternary ammonio synthetic detergent has the general formula:

wherein R is an alkyl radical containing from about to about 18 carbon atoms.

6. The composition of claim 1 wherein the soap to zwitterionic synthetic detergent ratio is about 1:1 and the combined weight of the soap and zwitterionic synthetic detergent is from about 9% to about 16% by weight of the finished detergent composition.

7. The composition of claim 1 wherein tetrapotassium pyrophosphate comprises from about 12% to about 15.5% by weight of the finished detergent composition.

8. The composition of claim 1 wherein borate ions comprise from about 1.75% to about 2.25% by weight of the detergent composition.

9. A stable, liquid detergent composition which is substantially free of amides and hydrotropes and which has a yield value of from about 10 to about 200 dynes per square centimeter consisting essentially of, by weight of the finished composition,

(1) fatty acid soap having an iodine value of from about to about 45; the cation of said soap being selected from the group consisting of monoethanolammonium, diethanolarnmonium and triethanolammonium cations; said soap having an acyl chain containing from about 14 to about 22 carbon atoms;

(2) a zwitterionic quaternary ammonio synthetic detergent having the general formula wherein R is an alkyl chain containing from about 10 to about 18 carbon atoms and R" is a radical selected from the group consisting of ethylene and hydroxyethylene; the ratio of soap to the zwitterionic synthetic detergent ranges from about 0.8210 to about 1.2: 1.0 and the combined weight of the soap and the zwitterionic synthetic detergent ranges from about 8% to about 20% by weight of the finished composition;

(3) from about 10% to about 17% of tetrapotassium pyrophosphate;

(4) from about 0% to about 3% borate ions;

(5) from about 0.1% to about 0.25% of an interpolymer of methyl vinyl ether and maleic anhydride in a molar ratio of about 1:1 having a specific viscosity of from about 0.1 to about 3.5 which is esterified with from about 0.1 to about 1 part by weight of a zwitterionic synthetic detergent per part of the interpolymer, said zwitterionic synthetic detergent having the general formula:

wherein R is an alkyl radical containing from about to about 18 carbon atoms; ('6) from 0% to about 40% of an insoluble, particulate material selected from the group consisting of water 5 insoluble abrasives and bactericides having particle diameters ranging from 1 micron to about 200 microns and a specific gravity of from about 0.5 to about 3.0; (7) from about 25% to about 85% water; and (8) sufficient strong base to adjust the pH of the com- 10 position to from about 7.5 to about 13.0.

10. The composition of claim 1 containing from about 7% to about by weight of a water insoluble abrasive having particle diameters ranging from about 1 15 micron to about 200 microns and a specific gravity of from about 0.5 to about 3.0.

11. The detergent composition of claim 1 wherein water comprises fromabout 55% to about 70% by weight of the finished composition.

12. The detergent composition of claim 1 wherein the pH is adjusted to from about 9 to about 12 by adding a strong base selected from the group consisting of sodium hydroxide and potassium hydroxide.

13. The detergent composition of claim 10 wherein the abrasive is selected from the group consisting of quartz, pumice, pumicite, talc, silica sand, china clay, bentonite, diatomaceous earth, whiting, feldspar and aluminum oxide.

References Cited UNITED STATES PATENTS 3,149,078 9/1964 Zmoda 252-137 3,351,557 11/1967 Almstead 252l06 3,346,504 10/1967 Herrmann 252137 3,346,873 10/1967 Herrmann 252137 3,324,038 6/1967 Chaffee 252152 3,328,309 6 /1967 Grifo 252-137 LEON D. ROSDOL, Primary Examiner D. L. ALBRECHT, Assistant Examiner U.S. Cl. X.R. 2521 17,

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 520 .818 Dated July 21, 1970 Inventor) Cushman Merlin Cambre It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

' Column 2, line 40 "diethanolammoniaum" should be '1 diethanolammonium Column '4, line 37, "R' should be R" Column 7, line 45, "part" should be parts Column 9, line 49 "10.3" should be 10.5 Column 10, line 23, estreified" should be esterified SiGNED MD SEALED JAN 5 1371 "In M0 Flcwhfl, I

m 3 can of Patflnta Awning Offic r 

